Quiz 3 Practice Questions

Question 1

On a busy shift at the hospital, you get told by the receptionist that an emergency was just added to your schedule. The patient is in rigor mortis but the owner claims the car died from fumes coming from the drying machine in the clinic. Which one of these statements would best describe rigor mortis for your medical file that will end up in court?

Answer 1

Rigor mortis is caused by loss of all energy compounds in the muscle so that energy is not available for relaxation

Question 2

A 3 year old Great Dane Border collie mic named Link presents to the clinic with: hypersalivation, miosis, frequent urination, diarrhea, vomiting and dyspnea. You strongly suspect tetraethyl pyrophosphate (organophosphate) poisoning, given the neighbors obsession with gardening. Which describes best the way organophosphate function?

Answer 2

Organophosphates inhibit cholinesterase, an enzyme that breaks down acetylcholine, a neurotransmitter that carries signals between nerves and muscles

Question 3

Stella is a 6 year old Golden Retriever, her owner is concerned with progressive weakness and exercise intolerance. Bow with difficulty swallowing and is regurgitating her food. After some diagnostics, Stella is low in Ach receptors, and you come to the conclusion that she has Myasthenia Gravis. What is the best explanation?

Answer 3

Due to the destruction of the Ach receptors, although produced, the neurotransmitter Ach will not be taken up within the neuromuscular junction, resulting in muscle weakness and poor contraction

Question 4

18 year old Bassett Hound mix named Todd, “sharp as a tack” per the owner, due to his diet of a bowl of ice cream every night after dinner. Calcium is important in neurotransmitters at the synaptic level due to:

Answer 4

Calcium causes a conformational change of synapsin I releasing the neurotransmitter from the cytoskeleton

Question 5

Cat suffering from chronic renal failure, will cause hypocalcemia, which os the following options will cause the spasms and tremors in the cat?

Answer 5

Flooding of Ach into the synaptic cleft causing over-stimulation of the muscles

Question 6

Hazlee (dog competition) presents after a competitive injury. You observe increased muscle tone due to build up of thyroxine levels. Thyroxine is one of the control methods of msucle sodium-potassium-ATPase during muscle activity. What is the resultant neurological effect in terms of Ach levels at the neuromuscular junction?

Answer 6

Decrease in AchE, increasing Ach leading to increased muscle contraction

Question 7

A 3 year old dog, Cleopatra, is unhappy with how her hindlimb twitches uncontrollably. There is likely something affecting the termination of a typical skeletal muscle twitch, which of the following factors is likely affected?

Answer 7

Calcium uptake by sarcoplasmic reticulum

Question 8

A 5 year old retriever named Bob presents with spastic paralysis and an old cut on his hind leg. He is suffering from tetanus, additional testing shows that his muscles are undergoing constant contraction with no chances of relaxation. Which of the following is the type of tetanus that Bob is suffering from?

Answer 8

Fused tetanus

Question 9

Sandrine is a Frenchie who has gained weight over the last year. Sandrine now goes for daily strenuous walks for hours at a time. Sandrine is tired and fatigued after exercise, but shakes it off. Which explains what type of skeletal muscle fibers are being utilized and why?

Answer 9

White/Fast; muscle fatigue and pain are caused because of the increase in lactic acid. Lactic acid increases as it was trying to compensate for the need for oxygen due to strenuous exercise, so it is relying on the quickest energy-generating mechanism

Question 10

Arrange the following events in skeletal muscle contraction in their order of occurrence.

Answer 10

5, 6, 4, 7, 1, 2, 3, and 8

Question 11

A 2 year old foxhound loves to run and prey. Which of the following contributes to prolonged muscle function for the dog to continue his high intensity exercise for so long?

Answer 11

Lactic acid

Question 12

When action potentials arrive from two or more presynaptic neurons on more than one postsynaptic neurons simultaneously, leading to an increased excitation of a postsynaptic neurons in a nerve fiber is known as:

Answer 12

Spatial summation of postsynaptic potential

Question 13

A local anesthetic, such as lidocaine, primarily prevents generation of action potential by inactivating:

Question 14

Which of the following is affected by genetic myasthenia gravis?

Question 15

Which of these proteins is responsible for docking during neurotransmitter release process in a neuron?

Question 16

Which is NOT an event in the conduction of impulse across a chemical synapse?

Question 17

At chemical synapse where acetylcholine is the neurotransmitter, 1. _____ and 2. _______ are found in the membrane of the 3. ______. Select option that best completes the above sentence.

Question 18

Excitatory postsynaptic potential (EPSP) would be facilitated by which of these?

Question 19

Myelination affects the conduction of nerve impulse along an axon in which of the following ways?

Question 20

Which of these is not a feature of graded potential in a neuron?

Question 21

Regarding the factors that affect neuronal membrane excitability, which of these would increase neuronal membrane excitability?